Lorries parked on the M20 during an Operation Stack in 2008. Maritime UK warned: ‘You could have a permanent Operation Stack for 20 miles.’
Photograph: Gareth Fuller/PA

Dover will face permanent traffic jams stretching 20 miles out from the port from March 2019 unless Theresa May agrees to the EU’s proposals for a Brexit transition period, the organisation representing the shipping industry and ports has said.

David Dingle, the chairman of Maritime UK, said lorry drivers could be stuck on the main approach roads to Dover for up to two days if there was no deal for a transition.

Referring to police procedures put in place to prevent gridlock on Kent’s roads, Dingle said: “You could have a permanent Operation Stack for 20 miles, it [the traffic] will just sit there.

“Drivers can be stuck for days, it [Stack] can be horrendous,” he said referring to a Stack operation in 2015 when long stretches of the M20 were closed for 24 days, with food left to rot on the motorway shoulder.

Ports and businesses have been calling for years for improvements on the M20, which is regularly hit by congestion, and Maritime UK fears this will now worsen as the government battles to unite over its Brexit vision.

“We are lost in politics,” Dingle said. “The meltdown will come back to the roll-on, roll-off ports,” he said. “We are shouting loudly about this, we have been for a while, but you do feel you are banging your head against a brick wall.”

He said it was not just the £100bn-a-year maritime industry that would be affected by delays, but also key businesses such as Japanese car manufacturers who rely on “just in time” car part delivery from the continent.

Consumers and supermarkets would also be affected, with 50% of the nation’s food coming from the continent and from Ireland, which is a huge supplier of dairy products, mushrooms and beef.

“Our message is: please, government, can you do this as quickly as possible because if there is no transition period the industry as a whole will be in trouble and the whole logistics chain will be in major trouble,” he said.

Last week the EU’s chief Brexit negotiator, Michel Barnier, said the transition was “not a given” after May laid down red lines on EU citizens coming to the UK after March 2019 and the right of the UK to object to new EU laws during the period.

Dingle said the French were already ahead of Britain in preparation for a no-deal Brexit, hiring customs officials for March next year for Calais, and the Belgians and Dutch were making similar contingency plans for Zeebrugge and Rotterdam ports.

Maritime UK is calling for an open-ended transition period, claiming it is pointless “book-ending” the implementation period when no one can make firm plans until the final withdrawal agreement is agreed in October.

One of the biggest challenges for cliff-fringed Dover port is lack of space for lorry checks. A £250m lorry park off the M20 was first proposed two years ago but has been the subject of a judicial review.

Dingle said the government’s infrastructure investment had focused on socially beneficial projects such as HS2, but it should be looking at investment in the M20 and approach roads to Southampton.

It could also look at developing new ports in such places as the Isle of Sheppey and Thanet in Kent, Maritime UK said.

Dingle’s comments were echoed by the UK Chamber of Shipping. “The planned series of speeches from senior ministers must not become an airing of public spats or a competition between Conservative rivals,” said Guy Platten, its chief executive.

“We urgently need a united government to project its authority, to grab these vital negotiations by the scruff of the neck” to “give absolute confidence” to business, he said, starting with a deal that keeps trade moving freely between the EU and the UK.

The Department for Exiting the European Union said it was confident a transition deal would be done. “There is clear agreement on both sides for an implementation period and we fully expect to agree a deal. This is in our mutual interest and is by far the most likely outcome.

“We are progressing our discussions with the European Commission with the aim of reaching agreement by the March European Council.”

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